The present invention relates generally to the cleaning of sheet articles and, more particularly, to an improved apparatus for washing specially configurated, curved glass sheets.
Bent or curved sheets of glass are commonly used as glazing closures in vehicles such as automobiles and the like. Sometimes, the bent or curved glass sheets forming these closures must be thoroughly washed or cleansed during the production thereof. For example, in the production of laminated safety glass windshields, two separate but complementary-shaped glass sheets are bonded to a plastic interlayer disposed therebetween to form the laminated structure. Before assembly of these component parts, the opposite surfaces of each glass sheet must be thoroughly washed and dried. Conventionally, the sheets are conveyed in an upright attitude through an enclosure wherein water or other cleaning fluids are sprayed onto the opposite surfaces of the sheets for washing the same. The sheets are then dried and advanced to an assembly room where the plastic interlayer is sandwiched between the two sheets of glass for laminating.
In another application, finished glazing closures forming automotive sidelights, backlights, and/or windshields having scratches or other surface imperfections often can be enlarged by rubbing or polishing the scratches out with a suitable abrasive compound. These reconditioned sheets must then be thoroughly cleansed, either manually or by conventional off-line washers, to remove all traces of the rubbing compound. Prior known washers include a conveyor for advancing wetted glass sheets in a horizontal path between elongated rotary brushes mounted on straight shafts extending transversely of the path of movement of the glass sheets or segmented brushes disposed in a staggered array, each of which engages only a portion of the glass sheets, but which collectively cover the entire width of the sheets passing therebetween. Where curved glass sheets are processed, the radial ends of the bristles forming the brushes are trimmed to define a contour complementary to the transverse configuration of the curved glass sheets. However, when differently shaped sheets are to be processed, these contoured brushes must be replaced by differently contoured brushes. It can be appreciated that the replacement of the several brushes each time a run of differently curved glass sheets is washed involves time-consuming labor as well as washer down-time to materially increase production costs. Moreover, a large inventory of differently sized and contoured brushes is necessary in order to accommodate the many varied shapes formed in these glazing closures.
In addition to the windshields, backlights and sidelights, recent automotive designs have also included sunroofs, i.e., specially configurated glass sheets that are fitted into the roof of a vehicle and often extend downwardly at a relatively sharp curvature into a portion of the upper side surfaces of the vehicle. These sunroofs generally are coated with a film of material adapted to reflect the major portion of the solar heat otherwise entering the interior of the vehicle while transmitting substantially all the light therethrough. Before coating these unusually shaped glass sheets, they must be absolutely clean and free of all foreign matter such as particulates, dust, human oils transmitted by manual handling etc. so that the coating material will properly adhere to the glass surface. Conventionally, these odd shaped glass sheets have been washed manually by hand to assure absolute cleaning. Again, such a manual operation seriously impairs efficiency in a mass production operation and adds materially to production costs.